Wiper device especially for the panes of motor vehicles

ABSTRACT

A wiper system is proposed, which is used to clean windows, in particular of motor vehicles. The wiper system has a driven wiper arm ( 12 ), guided on the motor vehicle and movable between two turning points, on whose free end ( 14 ), a pivot bolt ( 36 ) retained thereon is disposed, whose pivot axis ( 38 ) extends transversely to the longitudinal axis of the wiper arm, essentially in the direction of motion (double arrow  22 ) of the wiper arm ( 12 ), on which pivot bolt a wiper blade ( 16 ) is supported that can be pivoted about the pivot axis ( 38 ) and pressed against the window ( 28 ), and the wiper system has means for securing the wiper blade to the pivot bolt, which means have stop faces ( 78 ), ( 86 ) disposed on the wiper blade transversely to the pivot axis and spaced apart from one another and pointing away from one another, which fittingly engage between securing faces ( 80, 81 ), facing one another, of the wiper arm ( 12 ). A simple and economical wiper system is obtained if the stop faces of the wiper blade are disposed on the two long sides of a coupling part ( 32 ) that is present on the wiper blade and has a bearing bore ( 34 ) for the pivot bolt ( 36 ); that one securing face of the wiper arm is a cheek region ( 80 ) oriented toward the wiper blade; and that the other securing face ( 81 ) is embodied on an extension ( 44 ), protruding from the bearing bore ( 34 ), of the pivot bolt ( 36 ), which extension engages the stop face ( 86 ), facing away from the wiper arm, of the wiper blade ( 16 ) from behind.

BACKGROUND OF THE INVENTION

The invention is based on a wiper system. In one known wiper system ofthis type (German Patent Disclosure DE 10 55 410 A1), the wiper arm andthe wiper blade are disposed side by side, in terms of a view toward thewindow to be wiped, or one after the other, in terms of the direction ofoperation of the wiper system. As a result, a lower structural heightfor the wiper system is attained than is possible ,n wiper systems inwhich the wiper arm is located above the wiper blade (DE 1505397 A1).The lesser structural height of the generic wiper system has advantagesin terms of the behavior of the wiper blade with regard to lifting awayfrom the window, especially at high vehicle speeds. In such a wipersystem, so that the wiper blade will be secured to the pivot bolt duringwiping operation, the pivot bolt disposed laterally on the wiper arm isprovided in its middle portion with an annular groove, into which leafspring, secured by one end to the wiper blade and deflectable counter tospring force, dips after the wiper blade has been mounted on the pivotbolt, and together with the side walls of the annular groove, thisguarantees the securing of the wiper blade to the wiper arm. The twolateral annular faces of the annular groove form the securing faces ofthe wiper arm, while the side edges of the leaf spring act as stop facesof the wiper blade. The disposition and embodiment of such securingmeans is expensive, because on the one hand the pivot bolt has to beprovided with the annular groove, and on the other, when a wiper bladeis replaced, the new wiper blade has to be re-equipped with a suitableleaf spring.

In another known wiper system (DE 26 40 399 A1), the pivot bolt and itssecuring means are disposed on the wiper blade and are lost when thewiper blade is replaced and must therefore be provided on each wiperblade.

SUMMARY OF THE INVENTION

In the wiper blade of the invention, the wiper blade supported on thepivot bolt is disposed with the lateral stop faces of the coupling partbetween the cheek region of the wiper arm and the extension located onthe free end of the pivot bolt and is thus secured in the direction ofthe pivot axis. Especially detent means on the wiper blade that are lostwhen a wiper blade is replaced are not needed, because their function istaken over by the long sides of the wiper blade that are always present,regardless of any separate coupling part.

In a refinement of the invention, the extension is solidly joined to thepivot bolt, and the bearing bore, on its jacket face, is provided with apush-through conduit that is adapted to the extension. This affords thecapability of making the pivot bolt from a solid, inelastic material,such as metal.

An embodiment of the invention that is especially operationally reliablecan be achieved if a plurality of extensions are disposed on the pivotbolt, and if the bearing bore, on its jacket face, has a plurality ofpush-through conduits, adapted to the extensions and corresponding innumber to the number of extensions.

If the stop face of the wiper blade is embodied on the bottom face of acountersunk feature that extends from the opening of the bore in thecircumferential direction and radially, which countersunk featureextends from the long side, remote from the wiper arm, of the couplingpart in the direction of the pivot axis, then the extension dips intothe countersunk feature. Hence the extension, which might be visually inthe way, is no longer visible.

If furthermore the countersunk feature is embodied in annular-segmentalfashion in the direction of the pivot axis, and the push-through conduitdischarges into the countersunk feature, then at least one segment endface can be used as a stop or limiting face for the oscillating motionof the wiper blade in one direction of oscillation.

Expediently, the push-through conduit discharges into the countersunkfeature near one annular-segmental end face, resulting in a definedmounting position for the wiper blade on the wiper arm.

In a refinement of the invention, the other annular-segmental end faceforms an oscillation limitation for the wiper blade supported on thepivot bolt. As a result, the wiper blade on the wiper arm, if it liftsaway from the window, cannot rotate approximately 180°, which means thewiper blade will not rest with its back on the window.

To assure a proper oscillating motion, which meets requirements, of thewiper blade on the pivot bolt, the segment angle is greater than theoscillating motion of the wiper blade about the pivot axis of the pivotbolt that occurs during wiping operation, plus the thickness of theextension.

So that the extension of the pivot bolt, which may protrude by a portionthereof from the countersunk feature, will not present any risk ofinjury to a person working with the wiper blade, for instance whencleaning the windshield by hand, the depth of the countersunk feature isat least as great as the height of the extension, measured in thedirection of the pivot axis.

An especially economical embodiment of the concept of the invention isattained by providing that the extension is embodied on the order of arectangular plate, one long side of which faces toward the pivot boltand is joined, crossing the pivot axis, to the pivot bolt, preferablyintegrally, and its length is greater than the diameter of the pivotbolt. At the two places where the extension protrudes past the diameterof the pivot bolt, one securing face of the wiper arm can then beembodied in a simple way.

If furthermore the coupling part of the wiper system is retained on theupper band face, remote from the window, of a bandlike-elongated,spring-elastic support element, and over at least a portion it restsflatly on the support element, and furthermore a rubber-elastic wiperstrip that can be placed against the window is disposed, parallel to thelongitudinal axis, on the lower band face, oriented toward the window,of the support element, in especially low, lightweight wiper blade thatis part of the wiper lever is obtained.

Further advantageous refinements and features of the invention aredisclosed in the ensuing description of an exemplary embodiment shown inthe associated drawing.

BRIEF DESCRIPTION OF THE DRAWINGS

Shown in the drawing are:

FIG. 1, a wiper system schematically shown in a side view;

FIG. 2, the wiper system of FIG. 1 in a plan view;

FIG. 3, a detail marked III in FIG. 1 of a wiper blade belonging to thewiper system, shown on a larger scale;

FIG. 4, a plan view on the arrangement of FIG. 3 in the direction of thearrow IV;

FIG. 5, a side view of the arrangement of FIG. 4 in the direction of thearrow V;

FIG. 6, a perspective view of the arrangement of FIG. 3;

FIG. 7, a perspective view of the end portion, provided with a pivotbolt, of a wiper arm belonging to the wiper system;

FIG. 8, the arrangement of FIGS. 6 and 7 in a preassembly positionoriented toward one another, seen from the back side and in perspective;

FIG. 9, the arrangement of FIG. 8 in an intermediate assembly position,in a side view; and

FIG. 10, the arrangement of FIG. 9 in the operating position.

DESCRIPTION OF THE EXEMPLARY EMBODIMENT

A wiper system of the invention includes a wiper lever 10 (FIGS. 1 and2), which has a driven wiper arm 12 on one end that is guided on themotor vehicle, not shown, and to whose free end 14 an elongated wiperblade 16 is pivotably connected. The wiper arm 12 is supported by itsother end 18 and can be swiveled back and forth between turning pointsabout a pendulum axis 20 in the direction of the double arrow 22. Thewiper blade 16 is moved transversely to its length across the window tobe wiped, and with a rubber-elastic wiper strip 24, it presses againstthe surface 26 of the window 28 to be wiped.

The wiper strip 24 is joined, parallel to the longitudinal axis, to abandlike-elongated, spring-elastic support element 30, on whose upperband face 29, facing away from the window, a coupling part 32 is seated(FIG. 8), by way of which the wiper blade 16 is pivotably connected tothe wiper arm 20. To that end, the coupling part 32, resting flatly onthe band face 29, is provided with a bearing bore 34 (FIGS. 3-5), whichserves to receive a pivot bolt 36 that is joined solidly to the wiperarm 12 laterally on the free end 14 thereof (FIG. 7). The pivot bolt 36,or the pivot axis 38 (FIG. 2), thus extends essentially in the directionof the pendulum or operating motion (double arrow 22) of the wiper lever10. As seen in FIG. 1, the surface 26 to be wiped of the window 28,which is represented by dot-dashed lines, is curved. Since the line 26is meant to represent the greatest curvature of the window surface, itis quite clear that the curvature of the still unstressed wiper blade16, resting with both ends on the window, is greater than the maximumcurvature of the window. In response to a contact pressure exerted viathe wiper arm 12 and acting in the direction of the arrow 40 (FIG. 1),the wiper blade presses over its entire length against the windowsurface 26 with its rubber-elastic wiper strip 24, disposed on the lowerband face 31 of the support element 30. A tension thus builds up in thespring-elastic support element 30 made of metal, and this assures both aproper contact of the wiper strip 24 with the window 28 over the entirelength of the wiper strip and a uniform distribution of the contactpressure. Since the window, which as a rule is curved spherically, doesnot represent a portion of a spherical surface, the wiper blade 16relative to the wiper arm 12 must be capable of constantly adaptingduring its wiping motion to the particular location and course of thewindow surface. The pivot connection 34, 36 that makes an oscillatingmotion (double arrow 41) possible is therefore necessary between thewiper arm and the wiper blade.

This pivot connection will now be explained in conjunction with FIGS.3-8. In FIGS. 6 and 8, only the upper region of the wiper blade 16 isshown, representing the connection between the coupling part 32 of thewiper strip 24 and the support element 30. To simplify the description,no further distinction will be made between the wiper strip 24 and thesupport element 30, since the connection between these two parts is ofno significance for the design of the pivot connection between the wiperblade 16 and the wiper arm 12.

The part on the wiper arm of the oscillating pivot connection is formedby the pivot bolt 36 and its particular embodiment. As seen from FIG. 7,a platelike extension 44 is disposed on the end face 42 of the pivotbolt 36; one long side 81 of this extension is oriented toward the pivotbolt 36 and is integrally joined to it. The disposition of the extension44 is made such that it crosses the longitudinal axis of the pivot bolt36, which at the same time forms the pivot axis 38 of the pivotconnection. The length 46 of the extension 44 is greater than thediameter of the pivot bolt 36, so that both of its ends protrude inwinglike fashion and dimensionally identically past the pivot bolt. Toenable the pivot bolt 36 to be introduced into the bearing bore 34 ofthe coupling part 32 in order to form the wiper lever 10, the bearingbore is provided on its jacket face 48 (FIG. 4) with two diametricallyopposed push-through conduits 50, whose width 52 (FIG. 3) is adapted tothe thickness 54 of the platelike extension 44 (FIG. 7) in such a waythat the ends of the wings protruding beyond the diameter of the pivotbolt 36 can be passed without problem through the push-through conduits50. This naturally also requires that the depth 56 (FIG. 5) of thepush-through conduits 50 (FIG. 5) be dimensioned such that the size ofthe bore diameter plus twice the depth 56, added together, is at leastas great as the length 46 of the platelike extension 44.

On its one side cheek 58, extending longitudinally of the wiper blade16, the coupling part 32 has a ringlike protrusion 60, which surroundsthe bearing bore 34. This protrusion can be formed for instance by anannular-collarlike extension of a prefabricated bearing bush that isseated in the coupling part 32. On its other long side or side cheek 62,the coupling part 32 has two diametrically opposed countersunk features64, which viewed in the direction of the pivot axis 38 are embodied inannular-segmental form (FIGS. 3 and 6). One of the two push-throughconduits 50 discharges into each of the two countersunk features64—which countersunk features extend radially to the bore 34 and in thecircumferential direction over a segment angle. The two countersunkfeatures are disposed such that the push-through conduits 50 eachdischarge into the respective countersunk feature 64 near oneannular-segmental end face 66. The other annular-segmental end faces 70,located away from the faces 66 by the amount of the segment angle 68,define the countersunk features 64 in the circumferential direction. Thedepth of the countersunk features 64 is at least as great as the height74 of the platelike extension 44, measured in the direction of the pivotaxis 38. The dimension 75 between the outer segmental faces is somewhatgreater than the length 46 of the extension 44.

The connection between the wiper arm 12 and the wiper blade 16 forforming the wiper lever 10 will now be explained, in conjunction withFIGS. 8-10. First, the two wiper lever parts 12 and 16 must be broughtcoaxially to one another into a position in which the extension 44, orin other words its two winglike protrusions, are aligned with therespective course of the push-through conduit 50 associated with it(FIG. 8). After that, the wiper blade is slipped in the direction of thearrow 76 onto the pivot bolt 36, whereupon the winglike ends of theextension 44 enter into their push-through conduits 50. Once the wiperblade 16, or its coupling part 32, with the end face 78 of theprotrusion 70 strikes a flat cheek region 80 (FIG. 7), oriented towardit, of the wiper arm 12, the platelike extension 44 of the pivot bolt 36has also emerged from the bearing bore 34 and is located with itswinglike ends in the region of the respective two annular-segmentalcountersunk features 64 (FIG. 9). By pivoting the wiper blade 16 in thedirection of the arrow 82 (FIG. 9), the wiper blade or the wiper lever10 is made to reach its operating position, in which the winglikeprotrusions depart from their push-through conduits 50 and assume anoperating position, shown in FIG. 10, once the wiper blade is placedagainst the window 20 to be wiped. To prevent unwanted noise duringwiper operation and to assure proper guidance of the wiper blade on thewiper arm, the dimension 84 (FIG. 4) from the end face 78 to the bottomfaces 68 of the countersunk features 64 is adapted carefully to thedimension 88 (FIG. 7) of the face 80 of the wiper arm 12 and thelongitudinal end faces 81, oriented toward this face, of the winglikeends. It is understood that to prevent overdeterminations, the segmentangle 68 in the oscillation direction (double arrow 41) is greater, byat least the thickness 54 of the extension 44, than the oscillatingmotion of the wiper blade about the pivot axis 38 that takes placeduring wiper operation. It is moreover clear that the two countersunkfeatures 64 must be disposed with respect to the two push-throughconduits 50 in such a way that a relative motion between the wiper arm12 and the wiper blade 16 is possible during wiper operation. Theannular-segmental end face 70 located away from the push-through conduit50 is disposed such that it forms an oscillation limitation for thewiper blade 16 supported on the pivot bolt 36. This prevents the wiperblade, if the wiper arm has been folded away from the window, fromrotating approximately 180° about the pivot axis into an incorrectlymounted position, in which—instead of the wiper strip 24—the couplingpart 32 is then oriented toward the window 28.

The platelike extension 44 of the pivot bolt 36 thus forms a securingmeans for the wiper blade, so that the wiper blade cannot separateunintentionally—for instance during wiper operation—from the wiper arm.These securing means include stop faces 78, 86 of the wiper blade 16,which are spaced apart transversely to the pivot axis 38 from oneanother by a spacing 84 and which fittingly engage between securingfaces 80 and 81, facing one another, of the wiper arm 12. The stop facesof the wiper blade are disposed on the two long sides of a coupling part32 that is present on the wiper blade and has a bearing bore 34 for thepivot bolt 36. One securing face of the wiper arm 12 is a cheek region80 facing toward the wiper blade. The other securing face of the wiperarm 12 is formed on the extension 44 of the pivot bolt 36, whichextension protrudes out of the bearing bore 34, by means of thelongitudinal end faces 81 (FIG. 8) of the extension 44 that are orientedtoward the cheek region 80 and that are engaged from behind by thebottom or stop face 86 of the wiper blade facing away from the wiperarm. These stop faces 86 of the wiper blade are formed by the bottomfaces 86 of the countersunk features 64, which faces cooperate with thefaces 81, oriented toward them, of the winglike ends of the extension44. By means of a suitable adaptation of the depth 72 of the countersunkfeatures to the height 74 of the platelike extension 44, it is assuredthat the platelike extension will rest entirely in the countersunkfeatures 64 and will not protrude from them. In order to remove thewiper blade 1 b from the wiper arm 12, the wiper blade is pivoted out ofits operating position (FIG. 9), counter to the arrow 82 in FIG. 9,until the extension 44 is aligned with the push-through conduits 50.After that, it can be pulled off the wiper arm 12, in the oppositedirection from the arrow 76 in FIG. 8.

1. A wiper system, in particular for motor vehicle windows, having a driven wiper arm, (12), guided on the motor vehicle and movable between two turning points, on which, and in particular on whose free end (14), a pivot bolt (36) retained thereon is disposed, whose pivot axis (38) extends transversely to the longitudinal axis of the wiper arm, essentially in the direction of motion (double arrow 22) of the wiper arm (12), on which pivot bolt a wiper blade (16) is supported that can be pivoted about the pivot axis (38) and pressed against the window (28), and the wiper system has means for securing the wiper blade to the pivot bolt, which means have stop faces, disposed on the wiper blade transversely to the pivot axis and spaced apart from one another and pointing away from one another, which fittingly engage between securing faces, facing one another, of the wiper arm, wherein the stop faces (78, 86) of the wiper blade are disposed on the two long sides of a coupling part (32) that is present on the wiper blade and has a bearing bore (34) for the pivot bolt (36); that one securing face of the wiper arm is a cheek region (80) oriented toward the wiper blade; and that the other securing face (81) is embodied on an extension (44) of the pivot bolt (38), which extension engages the stop face (86), facing away from the wiper arm, of the wiper blade (16) from behind, and wherein the stop face of the wiper blade is embodied on the bottom face (86) of a countersunk feature (64) that extends from the opening of the bore in the circumferential direction and radially, which countersunk feature extends from the long side (62), remote from the wiper arm (12), of the coupling part (30) in the direction of the pivot axis.
 2. The wiper system of claim 1, wherein the extension (44) is solidly joined to the pivot bolt (36); and that the bearing bore (34), on its jacket face (48), is provided with a push-through conduit (50) that is adapted to the extension.
 3. The wiper system of claim 1, wherein a plurality of extensions are disposed on the pivot bolt (36); and that the bearing bore (34), on its jacket face (48), has a plurality of push-through conduits (50), adapted to the extensions and corresponding in number to the number of extensions.
 4. The wiper system of claim 1, wherein the countersunk feature (64) is embodied in annular-segmental fashion in the direction of the pivot axis (38); and that the push-through conduit (50) discharges into the countersunk feature.
 5. The wiper system of claim 4, therein the push-through conduit (50) discharges into the countersunk feature (64) near one annular-segmental end face (66).
 6. The wiper system of claim 5, wherein the other annular-segmental end face (70) forms an oscillation limitation for the wiper blade (16) supported on the pivot bolt (36).
 7. The wiper system of claim 5, wherein the segment angle (68) is greater than the oscillating motion of the wiper blade (16) about the pivot axis (38) of the pivot bolt (36) that occurs during wiping operation.
 8. The wiper system of claim 1, therein a depth (72) of the counter sunk feature (64) is at least as great as the height (74) of the extension (44), measured in the direction of the pivot axis (38).
 9. The wiper system of claim 1, wherein the coupling part (32) is retained on the upper band face (29), remote from the window (28), of a bandlike-elongated, spring-elastic support element (30), and over at least a portion it rests flatly on the support element; and that a rubber-elastic wiperstrip (24) that can be placed against the window is disposed, parallel to the longitudinal axis, on the lower band face (31), oriented toward the window (28), of the support element (30).
 10. A wiper system, in particular for motor vehicle windows, having a driven wiper arm (12), guided on the motor vehicle and movable between two turning points, on which, and in particular on whose free end (14), a pivot bolt (36) retained thereon is disposed, whose pivot axis (38) extends transversely to the longitudinal axis of the wiper arm, essentially in the direction of motion (double arrow 22) of the wiper arm (12), on which pivot bolt a wiper blade (16) is supported that can be pivoted about the pivot axis (38) and pressed against the window (28), and the wiper system has means for securing the wiper blade to the pivot bolt, which means have stop faces, disposed on the wiper blade transversely to the pivot axis and spaced apart from one another and pointing away from one another, which fittingly engage between securing faces, facing one another, of the wiper arm, wherein the stop faces (78, 86) of the wiper blade are disposed on the two long sides of a coupling part (32) that is present on the wiper blade and has a bearing bore (34) for the pivot bolt (36); that one securing face of the wiper arm is a cheek region (80) oriented toward the wiper blade; and that the other securing face (81) is embodied on an extension (44) of the pivot bolt (36), which extension engages the stop face (86), facing away from the wiper arm, of the wiper blade (16) from behind, and wherein the extension (44) is configured as rectangular plate, one long side (81) of which faces toward the pivot bolt (36) and is joined, crossing the pivot axis, to the pivot bolt, preferably integrally, and its length (46) is greater than diameter of the pivot bolt (36).
 11. A wiper blade assembly for a wiper system, in particular for motor vehicle windows, having a driven wiper arm (12), guided on the motor vehicle and movable between two turning points, on which, and in particular on whose free end (14), a pivot bolt (36) retained thereon is disposed, whose pivot axis (38) extends transversely to the longitudinal axis of the wiper arm, essentially in the direction of motion (double arrow 22) of the wiper arm (12), the wiper blade assembly comprising a wiper blade (16) supportable on the pivot bolt pivotally about the pivot axis (38) and pressed against the window (28), and means for securing the wiper blade to the pivot bolt, which means have stop faces disposed on the wiper blade transversely to the pivot axis and spaced apart from one another and pointing away from one another, which are fittingly engageable between securing faces, facing one another, of the wiper arm, wherein the stop faces (78, 86) of the wiper blade are disposed on the two long sides of a coupling part (32) that is present on the wiper blade and has a bearing bore (34) for the pivot bolt (36), and wherein one of the stop faces of the wiper blade is embodied on the bottom face (86) of a countersunk feature (64) that extends from the opening of the bore in the circumferential direction and radially, which countersunk feature extends from the long side (62), remote from the wiper arm (12), of the coupling part (30) in the direction of the pivot axis. 